An army dog stands up as retiring soldiers salute their guard post before retirement in Suqian, Jiangsu province, China on November 29, 2017. (Photo by Reuters/China Stringer Network)

Revellers take part in the annual Gay Pride parade along Paulista Avenue in Sao Paulo, Brazil, May 29, 2016. (Photo by Nacho Doce/Reuters)

A boat sails behind a woman looking through binoculars as she sits on a cliff on a sunny day in Sydney, Australia, May 29, 2016. (Photo by David Gray/Reuters)

A crew members walks on the flight deck past Super Etendard fighter jets aboard France's Charles de Gaulle aircraft carrier on missino in the Gulf, January 29, 2016. (Photo by Philippe Wojazer/Reuters)

A cockfight is seen at an event organised to celebrate the Lunar New Year and the year of the Rooster on the outskirts of Bangkok, Thailand January 29, 2017. (Photo by Jorge Silva/Reuters)

A donkey carrying sacks of coal walks through the narrow tunnels of a coal mine, in Choa Saidan Shah in Punjab province April 29, 2014. Coal miners in Chao Saidan Shah use donkeys to transport coal from the depths of the mines to the surface. (Photo by Sara Farid/Reuters)

Chen Ruolin of China performs a jump during the mixed team event final at the Aquatics World Championships in Kazan, Russia July 29, 2015. (Photo by Stefan Wermuth/Reuters)

Prostitutes working on 10th Ave in New York, USA on June 29, 1997. (Photo by Jon Naso/NY Daily News Archive via Getty Images)